Intermittent drilling and tapping machine



R. M. GALLOWAY INTERMITTENT DRILLING AND TAPPING MACHINE Filed Jan. 17. 1927 6 Sheets-Sheet 1 MTM@- Feb. 5, 1929. 1,700,980

R. M. GALLowAY INTERMTTENT DRILLING AND TAPPING MACHINE Filed Jan. 17, 192'? Feb. 5, 1929.

R. M. GALLowAY INTERKITTENT DRILLING AND TAPPING MACHINE Filed Jan. 17, 1927 6 ShetS-Sheet 3 @Hoz/nm A i um #Maxam Feb. s, 1929. 1,700,980

R. M. GALLOWAY IN'xBRuITTI-:NT DRILLING AND TAPPING MACHINE Filed Jan. 17, 1927 6 Sheets-Sheet 4 g5 au Fa] 771, @WJ WTIGICLM Feb. 5, 1929. 1,700,980

R. M. GALLOWAY INTRMITTENT DRILLING AND TAPPING MACHINE Filed .17, 192'? 6 Sheets-Sheet 5 CQ J 4 i H I 335% @1Mo/Imc? y Feb. 5, 1929. 1,700,980

R. M. GALLowAY INTERMITTENT DRILLING AND TAPPING MACHINE @Hoi/maj Patented Feb. 5, 1929.

UNITED STATES PATENT OFFICE.

ROBERT M. GALLOWAY, OF RICHMOND, INDIANA, ASSIGNOR TO THE NATIONAL AUTO- MATIC TOOL COMPANY, OF RICHMOND, INDIANA, A CORPORATION OF INDIANA.

INTERMITTENT DRILLING AND TAPPING MACHINE.

Application filed January 17, 1927.

Single-purpose machine tools, i. e. machine tools equipped to perform only a single operation, are generally conceded to be more practical and efficient than the necessarily more complicated and more expensive universal machine tools which are adapted to perform various machining operations. Therefore single-purpose machine tools are usually used wherever the number of similar operations to be performed is sutliciently great to warrant the provision of an indi vidual machine for that operation such for example, as in quantity production, where a machine may be used continuously day in and day out for performing repeatedly a single operation.

This inventien has for an object to render available a machine tool which vill have all of the advantages of a single-purpose machine tool and which in addition, may be utiliiced to perform different machining operations, such for example as vdrilling and tapping. lt is well understood that different maeliining operations require different rates of relative noven'ient between the work and the tool and in certain operations this relative movement is in transverse direct-ions. Suppose, for example, that' drilling:l and tapping of a hole o t predeterminedsize is to be performed ellicient'iy; when drilling the tool must be rotated at a relativelyv rapid rate and fed into the n'orlt at a relatively slow rate, whereas in tapping the requirements are reversed and the rotation must be relativelv slow while the feed must be relatively rapid.

This invention therefore has for another obieet to provide :l drilling and tapping machine in which the drills and taps will be rotated and translateffl at speeds most etlii-ient for their individual operations and to provide simplified mechanisms, which are po 'n action. to produce these movelllll .,ti'iother object of the invention is to provide. in a machine tool. two trains of mechansm. om for rotating and feedimi tool-spindles at a rate suitable for drilling and another train adapted to rotate and feed tool- :-1pindles at a rate suitable for tapping and so to combine the two trains that one set of ndhw may receive one of its movements from the mechanism which actuates the other ser of ..pmlle;-f therein reducing to a minimum he :stunning nireliani-tix.

Serial No. 161,510.

Still another object is to provide improved and simplified mechanism, devoid of trips, dogs, etc. for giving the tap-spindles a predetermined number of rotations in a forward direction to thread the taps into the work and than reversing the direction of rotation pflthe taps to unscrew them from the tapped 110 QS.

Another object of the invention is to provide an improved machine frame adapted to support and house the mechanism above referred to and which may be built up of closed sections which when assembled. constitute a single closed and substantially oil tight structure; and to provide means continuously to lubricate all of the, mechanism therein.

Another object of the invention is to provide a machine tool in which differently equipped tool heads readily may be secured upon a supporting column with the initial gears of two driving trains in driving` relation with two drive shafts supported by the column.

Other objects and advantages will be in part indicated in the following description and in part rendered apparent therefrom in connection with the annexed drawings.

To enable other skilled in the art so fully to apprehend the underlying features hereof that they may embody the same in the various ways contemplated by this invention, drawings depicting a preferred typical construction have been annexed as a part of this disclosure and, in such drawings, like characters of reference denote corresponding parts throughout all the views of which Figure 1 is a vertical sectional view of a machine tool embodying the present invention. Fig. 2 is a top view thereof with the cover-plate removed. Fig. 3 is a view substantially on the line 3-3 of Fig. l. Fig. 4 is a detail section on the line t-*t of Fig. 3. Fig. 5 is a horizontal section through the clutch mechanism shown in Fig. 1. Fig. 6 is a detail sectional view showing the upper ends of two drill-spindles and the means for giving` them their axial movements. Fig. 7 is a detail section showing a cam which effects down feed of the drill spindles. and the parts associated therewith. Fig. 7a is a detail View showing the upper end of the column and one of the interet] exigeante, tool heads rhereahnvti with the initial emits nt the mp spindle and drill spindle driving trains about to be placed upon the driving shafts therefor. Fig. 8 is a front view of an interchangeable drilling and tapping machine also embodying' the present invention, the machine being shown, for the purpose of illustration, as equipped with two tap-spindles and a single drill-spindle but it is to be understood that in practice it will be equipped with all drillspindles or all tap-spindles, as will hereinafter be explained. Fig. 9 is a plan of the machine shown in Fig. 8. Fig. 1() is a central vertical section thereof. Fig. 11 is a view on the line 11-11 of 10.y Fig. 12 is a section on the line 124-12 of Fig. 1() showing both the tap-spindle drive and the drill-spindle drive later to be described. Fig'. 13 is a Vertical section of the upper portion of a second modified three-spindle machine embodying the present invention and in which all of the spindles may be rotated unidirectionally for a drilling operation. or they all may he given forward and reverse rotations for tapping; or certain ones may be rotated forwardly and reversely for tapping simultaneously with a unidirectional rotation of another. which latter' may he used for drilling. Fig. 14 is a section substantially on the line 14-14 of Fig. 13.

Referring now more particularly to the embodiment of the invention illustrated in Figs. 1 to 7 inclusive, the machine tool is provided with four drill spindles, a.. e. and (I and four tap spindles e. g, and /L arranged similarly to the drill spindles. In operation, the Work is presented first to the action of drills, carried by the drill spindles, where it is drilled. then itis placed beneath the tap spindles and the drilled holes are simultaneously tapped, after which the work is removed from the machine. This presentation of the work successively to the drills and taps may be effected in any suitable way. such tor example. as bv having the work held in suitable workholders mounted upon a rotatable work-table which may be indexed either manually or luy power. Inasmuch as the work-holders and work-table form no part of the present invention illustration and description thereof is deemed unnecessary. lt will suffice to say that such a table may be supported upon a bed plate C later to he referred to. The machine tool shown in Fig'. 1 comprises a closed base comprising' sections .1 and B. The section A is arranged to hold cutting compound which is supplied to the drills and taps by means of a motor driven pump l. arranged in a rearward extension 1 of the hase. and which forces the compound through a discharge pipe 2 and through nozzles 3 to the tools. Upon this section is secured as by screws 4 (only one of which is shown) the closed box-like section or unit B which houses material part of the mechanism for giving the tap-spindles forward and reverse rotations. This unit is oil-tight and serves as a reservoir for lubricant which is pumped to the upper portion of the machine tool by a pump L and allowed to flow down over all of the actuating mechanism thereby lubricating t-he same and eventually returning to the reservoir. Secured upon the portion of the unit B and forming a cover' therefor is a bedplate C adapted to support the work-table hereinbefore referred to.

A hollow column section D is secured upon the bed-plate and is adapted to receive and support, at its upper end. any one of a plurality of interchangeable oil-tight heads E. each consisting of a gear chest F containing suitable drill and tap spindle rotating gear trains and a cap section Gr which contains the means for giving the tap and drill spindles their axial movements. The arrangement of the drill and tap spindles maybe different in each of the various heads to correspond to tl e arrangement of holes to be drilled and tapped in various work pieces but in allotthese heads the initial driving gear of the drill and tap spindle trains will be similarly located and adapted readily to be engaged with the upper ends ot' drive shafts supported by the colmun.

Dr?? spindle rolt/ating mechanism.

Power to rotate and translate the drill and tap spindles is provided by a motor M mounted upon the rear of the column D. A bevel gear 5 secured upon the motor shaft meshes with and drives continuously a similar gear 6 keyed to a. shaft 7 journaled in bearings 8 and 9 provided by the units D and C respectively. For the purpose of facilitating assembling of the machine tool this shaftr preferably made in two sections 7 and 7h which meet within the hub (3" of the gear (i and adjacent the key 10 which etl'ects a drive from the gear to beth the sections T* and Th. Splined upon th(` upper end of the shaft section Ta. and supported within the gear-chest F. is a gear 11 constituting the initial `:rear of a gear train which rotates the drill-spindles continuously in one direction from power supplied by the motor M. As shown in Fig. 2 power from the gear 1l flows through gears 12. 13. 14 and 15 to pinions 1o and 1T secured upon the (hill-spindles and d, A. gear 18, driven by the gear 15. mesh with and drives a gear 19 hich in turn rotates pinions 2U and 21 secured upon the drill spindles o, and c, The gears 15 and 19 are wide face gears which permit the spindles 1. c. and f. and the pinions thereon. to be moved axially. by means later to he described, to give the drills their feed and return movements without disturbing the driving` connections between the gears 15 and 19 and the pinions. The gears 12, 13, 14, 15. 18 and 19 are rotatably journaled on short shafts 12a, 13a, 14a, 15a, 18a and 19a. respectively. secured atI their lower ends in the lower wall of the gear casing' F and having plate 62, whereby oscillation of the shaft 64 in one direction causes the arm 68 to depress the plate and therewith the drill spindles to feed the drills into the work as they are rotated by means hereinbefore described. Oscillation of the shaft in the opposite direction raises the free end of the arm 68 and the coil springs G3 act to raise the drill spindles to withdraw the drills from the work. The shaft G-l also has fixed to it a second arm 69 which projects oppositely to the arm 68 and carries at its free end a roller 7() which rests upon the upper inclined surface of a reciprocatory cam Tl. This cam is preferably formed on a slide-bar T2. translatably mounted in bearing;` bosses 723. and has rack teeth T4 formed on one side thereof. A pinion T5. keyed to rotate in reverse directions with the gear 44. meshes with the rack teeth 74 and serves a shaft 43 is rotated to effect forward tap rotation) to translate the bar T2 to the left as viewed in Fig. 7. This movement 0f the bar elevates the free end of the arm 69 thereby depressing the arm 6F and consequently the plate GQ and drill spindles; the arms 68 and 69 constituting in effect a lever of the first order. llevcrsc rotation of the tap rotating mechanism, and thereby the pinion 75. translates the bar T2 in the opposite direction and permits the springs (33 to elevate the drill spindles.

Control for tcp rotating and die?? feeding mechanism.

As hereinbefore stated the shaft 7 and worm wheel 23 are rotated continuously from the motor M and motion is transmitted to the shaft 25 and the tap rotating mechanism only when the teeth 24X and 28X of the clutch elements 24 and 28 are engaged. To effect engagement and disengagement of thc clutch teeth there is rotatably and translatably journaled in the section B a shaft T6 havin;r securcd to its forward end an actuating` lever 77. The rear end of this shaft has rotatably but non-translatal'ily secured to it (as by being held between pinned collars 7S and T9) a gear shifter S0 formed with spaced arms which carry pins or rollers Si fitted within an annular groove S2 in the clutch clement QS. A combined tension and expansile spring 93, surrounding the .shaft T6 and fitted within recess 84 in the bearing' bracket 85 has its ends attached to the brack t and to the collar T9 and normally tends to shift the shaft axially to engage the clutch teeth. This spring also tends to rotate the shaft in a counterclockwisc direction as viewed in Fig. t but permits clockwise rotation thereof t'or a purpose later to be explained.

Upon completion of a drilling` and tapping operation the clutch teeth 24X and 28X are automatically disengaged. and the machine is brought to rest. This is effected by means now to be described. To the shaft 76 is Secured a collar or sleeve 86 provided with an upstanding arm 8T and downwardly and outwardly extending arm 88. the latter arm being adapted to Contact with the lower horizontal wall b of the section B to limit the counter clockwise rotation of the shaft 76. Attached to the hub 39 ot the rear segment is an arm Si) to which is secured a heavy spring member 90 adapted, as the segment approaches its cxtreme oscillation in the direction which unscrews the taps from the work, to engage the upstanding arm Si' of the collar tt thereby shiftiln;` the shaft 76 axially toward the t'ront of the machine. against the action of the spring` 83 and disengaging the clutch teeth 24X and 28X and bringing the machine to rest. A subsequent operation may be started by swingingp the lever TT clockwise thereby rotating' the shaft 76 and shifting'the arm Si' out of contact with the spring member. and then pushing' inwardly on the lever to shift the shaft 76 axially again to engage the clutch teeth 24X and 28".

Lubricating ai/Szcm.

All of the above described spindle rotating and feeding` mechanisms arc kept continuously and generously lubricated by the action of a gear pump L located within a depressed portion of the section B and operated continuously by means of a pinion 9i. on the shaft section 7b. which drives a gear 92 and thereby actuates the pump. An exhaust pipe 93 eX- tends upwardly from the pump and transports lubricant into the cap section G. This section fills with lubricant until it has reached the level of an overflow pipe 9i whereupon it flows downwardly through the overtiow pipe and is received in the gear chest F. Likewise anV overflow pipe 95 is so arranged that after the gear chest has substantially tilled with lubricant. the lubricant passes through the pipe and downwardly through the column section l) and is finally returned to the section P where it is again taken up by the pump L and forced up into the cap section, thus a continuously acting circulatory system is provided which generously lubricates all of the operating mechanism of the machine tool.

It is to be understood that although this inv'ention is disclosed as embodied in an upright drilling and tapping machine it is also adaptable to various other types of machines. such. for example. as that type in which the tool spindles are disposed horizontally. Vhen embodied in the latter type the lubricating system may either be modified to suit the requirements or eliminated.

The machine tool illustrated in Figs. 8 to l2, inclusive, embodies the generic features of the machine tool shown in Figs. 1 to 7 above described and also includes important fea tures not disclosed in Figs. 1 to 7. The two machine tools are similar in that they both include a segment-actuated gear train to rotate tap spindles and a separate gear train to rotate drill spindles. They are also similar in that in both the feed of the tap spindles is effected by lead screws and lead nuts and the drill spindles are reciprocated in one direction by a rock arm actuated by the tapspindle rotating mechanism and in the opposite direction by springs. The latter machine tool however differs from the former in that it is provided at any one time with only a single series of spindles, i. e. either drill spindles or tap spindles and means is provided whereby the machine selectively may be equipped with either type of spindles. Also the modified machine is provided with a mechanically indexed work table for successively presenting a work piece to the action of tools carried by the three tool spindles.

Referring more particularly to the drawings the modified machine is disclosed as comprising a closed base section H, a bed plate I, a column J, and a head K. A work-supporting table T is rotatably supported upon the:

bed plate I and is automatically indexed by mechanism within the base section H, successively to present the work piece to the action of the farious tools. As shown in Figs. 8`r and 10 the modified machine is equipped with one drill spindle and two tap spindles but it is lo be understood that this is merely for the purpose of illustration and that in practice all of the spindles will be used for d rillingf or they will all be used for tapping and the appropriate spindle rotating and traiislating means will be rendered effective. This provides practically two single purpose machines either of which may be used at the will of the operator.

Dit??? spin/Ue rotating mechanism.

ln Fic; 12 the spindles are designated 2'. and .71. l/Vhen these spindles are used for drilling' they are rotated unidireetionally by mechanism now to be described. Upon the iin-:ler side of the section H there is secured a motor vlvl to the armature shaft of which is fired a double `egroove pulley 101. A belt 102. driven by this pulley, is trained over idler pulleys 103 and 1021. secured upon a shaft 105 rotatably journaled in bracket 106, and about a pulley 107. This latter pulley is fixed upon a shaft 108 (journaled in bearings 109 and 110 provided by the head K) upon which is secured a gear 111 forming' the initial gear of a drill-spindle rotating ,gear train. Power from the gear 111 flows through intermeshi nears 112, 113 and 11-1 to pinions 115 and o secured respectively upon the spindles fi and 3. The spindle Il" is also driven from this near train through a gear 117 in mesh with flic pinion 116 and which drives a pinion 118 on said spindle. The gears 112, 113, 114, and

117 are journaled upon shafts 1123', 113, 114a and 117u respectively sustained by the head K. The gears 111 and 117 are wide face 2@ears which permit the pinions 115. 116 and 118 to be moved axially with the drill-spindles without interrupting the spindle drive.

From the foregoinga it will be perceived that the spindles fi, y'. and /l are rotated continuously in one direction from the motor M when they are used for drilling. For certain reasons it may be advisable to use one type of spindle for drilling and another type for tapping and it is to be understood that the one set of spindles may be removed from the head and another set of spindles inserted when it is desired to change from drilling to tapping' and conversely. This conveniently may be done by releasing the pinions 115, 11G and 118 from their respective spindles, dropping; the spindles out of their bearings, inserting spindles of a different type, and securing' the pinions 115, 116 and 118 thereto.

Tap spindle rotatif/Lg mechanism.

When the machine is 'to be used for tapping` it is necessary that the spindles, and the taps carried thereby. be rotated first in one direction to thread the taps into the work and then in the opposite direction to unserew the taps from the threaded holes. This forward and reverse drive is also effected from the motor M but by mechanism independent of the drill spindle drive above described except that for convenience the intermediate gears 1111 and 117 may be utilized to transmit motion from one spindle to another. lVhen the tap rotating' mechanism is rendered effective the drill rotating mechanism is rendered ineffective. This may be effected by throwingV the belt 102 off the pulley 101. Power to rotate the spindles forwardly and reversely is taken from the motor M by a belt 119 which is driven by the pulley 101 and which drives a pulley 120 fixed upon a shaft 121 journaled in a bearing 122 provided by the base section H and a bearing 123 provided by a bracket 121 secured in said section. Upon this shaft is secured a worm 125 which meshes with and drives a worm wheel 126 fixed upon a shaft 127 journaled vertically in the section H. Upon the upper end of the shaft 127 is secured a crank arm 128 which carries a roller 129 fitted within a slot 130 formed in a gear segment 131 having its hub 132 journaled upon a shaft 133 rotatably journaled in the section H. At its periphery the segment 131 is provided with teeth 13-1 which mesh with a pinion 135 fixed upon a shaft 136 rotatably Iiournaled in bearings 137 and 138 provided by the bed plate and the column respectively. To this shaft is also secured a gear 139 which meshes with and drives a gear 1-10 splined upon a shaft 111 journaled in bearings 1411*l and 112 provided respectively by the bed plate and the Column. llivhen the machine is being used for tapping thegear 140 is shifted into mesh with the gear 139 fixed upon the shaft 141. A shifter 145 is provided for shifting the gear 140 into and out of mesh with the gear 139.

It will readily be perceived that continuous rotation of the crank arm 128 about the axis of the shaft 127 will, through the action of the roller 129 on the walls of the slot 130, cause the segment 131 to oscillate back and forth a predetermined extent about the axis of the shaft 133 and these movements of the segment will cause the pinion 135, shaft 136` gears 139 and 140, and shaft 141 to be rotated first in one direction and then in the reverse direction. These oppositely directed rotations are transmitted to the tap-spindles by a suitable gear train located within the head K. This gear-train is shown in full and dotted lines in Figs. 12 and 9, respectively, and begins with a gear 146 keyed to turn with the shaft 141 and which meshes with and drives a wide face gear 147 (see Fig. 10) which in turn meshes with the pinion 116 h-ereinbefore referred to, but which in the presen-t instance is secured upon a tap spindle rotatably and translatably journaled in the head K. Rotary motion is now transmitted to the spindles and 7c (which are now tap spindles) from the pinion 116 on the tap spindle 7' by means of the intermediate gears 114 and 117 meshing with the pinions 116-115 and 116-118 respectively. Motion will now flow backwardly through gears 113. 112 and 111 and rotate the pulley 107 but this is merely idle rotation, the belt 102 having been disconnected therefrom.

Likewise when the spindles are used for drilling as hereinbefore described the gears 147'. 146 and shaft 141 are rotated from the drill spindle drive. This motion, however, does not flow backwardly any further than the shaft 141 as the gear 140 is then disengaged from the gear 139.

Tap spindle feeding means.

As the tap spindles are rotated forwardly by movement of the segment 131 in one direction they are fed downwardly .to cause the taps carried hereby to be forced into the work. To .produce a perfect thread it is desirable that the downward movement per rotation correspond in extent to the lead of the tap. This is effected by having the upper end of each of the tap spindles formed as a lead screw 148 of the same pitch as the tap to be used and having these lead-screws threaded through stationary lead-nuts 149 secured upon the upper wall of the head K. As the tap rotating mechanism is reversed, by a reverse movement of the segment, the lead screw will be rotated in the reverse direction and the tap will be unscrewed and withdrawn from the tapped hole.

DM'JZ spindle feeding means.

It is well understood that as the drill spindles are rotated forwardly they must be given an axial movementI toward the work to make the drills feed thereinto. This invention provides improved means for effecting this feeding moven'ient. (.)n the underside of the segment 131 and preferably integral therewith there is provided an arcuate cam 150 (see Figs. 10 and 11) which, when the Segment is rotated in one direction, acts to depress a roller 151, rotatably secured upon the free end of a rock yarm 152 fixed upon one end of a rock shaft 153. journaled in bearings provided by the base sei-tion H. Another arm 154 is secured upon the other end of the shaft 153 and this arm is connected by a link 155 with a third roi-k arm 156 fixed upon a rockshaft 157 journaled in a bearing bracket 158 secured upon the upper wall of the head K. Also secured to the shaft 157 are three drill spindle depressing arms 15S" (only one is shown) the free ends of which bear upon caps 159 seated upon anti-friction thrust bearings 160 secured upon the upper' ends of the drill spindles. Springs 161 interposed between the upper wall of the head K and the thrust hearings normally serve to maintain the drill spindles. and the drills carried thereby elevated but permit them to be depressed by the arms 158l under the action of the ram V150. Thus it will be seen that the segment nieves in one direction the drill spindles will be depressed and as the segment moves in the opposite direction and the cam recedes from beneath the roller 151 the spindles will be elevated by the action of the springs 160. When the spindles are used for tappingl the above described drill feed is rendered ineffective in any suitable way such for example as by releasing the arm 154 from the shaft 153.

To afford rigidity and positivcness in action the segment is held against moving laterally undeil the pressure of the cam 150 on the roller 151. This is effected by forming an arcuate rib 162 on the upper surface of the segment 131 above the cam 150 and a cooperating like rib 163 against which the rib 162 is adapted to bear on lthe underside of the bed-plate I which forms a part of the machine frame. Thus it will be seen the lateral pressure of theY roller 151 on the cam 150 is resisted by the frame of the machine thereby relieving the segment bearing of strain.

The present machine is particularly useful where it is desired to drill or tap, in pieces of work. a plurality of holes so closely nested as to make it implacticable to drill or tap them all in a single operation. In work of this nature all of the holes may be drilled or tapped by successively presenting the workpiece to the action of tools secured in the drill spindles lc, j, and z'. This successive presentation of the work to the drills is preferably effected by securing the work-piece in a suitable work holder fixed upon the rotatable table T and causing the table to be indexed after each drilling operation.

Indexingy movements are given to the work table preferably by a Geneva mechanism and a series of change gears combined therewith to vary the angular movement of the table from a constant movement of the (teneva mechanism. A Geneva star wheel 104 is rotatably journaled about the shaft 133 and is acted upon by a stud or roller 165 carried by the worm wheel 12(i whereby the star wheel is given a rotation of sixty degrees upon each complete rotation of the worn'i-wheel and consequently each reciprocatiou of the toolspindles. Fixed to the star wheel and rotating' therewith is a gear 100 which drives a gear 107 rotatal'ily jouruaed about the shaft 127. This last named gear has secured to it a` stub shaft 108 upon which is removably secured one of a pair of interclningeable pickotf change gears 169-170 of which the latter is removably secured upon the shaft 133. The 'haft 133 has the work table 'l' secured to its upper end and therefore the table pai-takes of the rotary motion of the shaft. By varying" the ratio of the pick-off change gears any desired extent of movement (between certain limits) may be given to the work-table. 1 segmental block 171 on the worm wheel 120 engages arcuate notches 172 in the periphery of the star wheel and prevents accidental movement of the work table and its rotating mechanism between indexing movements. The pick-off change gears 167-170 are preferabl v enclosed within a sub-casinar 172 removably secured to the underside of the base section H.

From the foregoing it will be perceived that this modified machine is adapted selectively to perform either drilling; or t-al'iping operations and when ufed for either operation it has all of the advantages of a single purpose machine, the tool rotating mechanism specific to the other operation being rendered ineffective.

Second modicatz'on.

Figs, 13 and 14 show a second modified machine embodying the present invention. This machine includes a desirable feature not embodied in the machines hereinbefore described, to wit; it provides means whereby certain ones of the spindles may be rotated in forward and in reverse directions for tapping. while another spindle is rotated continuously in one direction. for drilling.

When all of the spindles are to be rotated unidirectionally the drive therefor flows from the pulley 107, shaft 108 and gear 111 to a gear 200 rotatably and translatably ournaled upon the upper end of the shaft 141. which in the present embodiment extends through the head K. The gear 200 meshes with and is slidable upon) a wide face gear 201 which through pinion 202` rotates the spindle z'. In the present instance the shaft 108 extends to the base of the column and is arranged coaxial with the shaft 13 'l'he spindles j and L' are nov.' rotated from the shaft 136 by means of a gear 203 rotatably and translatahly journaled on the shaft- 108 but adapted 'io be clutched to rotate either with the shaft 10h` or with the shalt 13' When the spindles and l; are to be used for drilling the gear 203 is shifted upwardly by a grear shifter 210 to engage i'; with a clutch member 21,1 and to release it 'from the shaft. 13%, and in this positie-n etl'ects a drive freni shaft 108 to the shaft 1-1-1 through the gear 203 and wide, faced gear 201 fixed to the last named shaft. The spindle j is then rotated unidireetionally through 5r-ins 203, 20.', shaft 14:1, gears 205, 200, and pinion 207, which rotation is transmitted to spindle through gear 208 and pinion 209.

Vt'hen it is desired successively to transmit forward and reverse rotation to the spindles the gear 203 is shifted downwardly to engage it with ehrt-uh member fixed to the shaft 130, and the gear 200 is shifted downwardly by shifter 213 to clutch it lo gear 205 (ail shown in dotted lines in Fig'. 13 Forward and reverse rotations then are transn'iitted to and spin-.iles and /`.4 from the. shaft 130 through ,gears 203. 21ml, shaft ttl, gears 205, 200, pinion 207, gear 203, and pinion 209; and to spindle i through gear 200 (new clutched to gear 205) gear 201 and pinion 202.

The spindle u' may lie rotated unidirectionally for drill'.i (while spindle-5 and ./x are rotated alternately forwardly and reversely) by first shifting' the gear 200 upwardly to disengage it from rear 205 and to engage it with gear 111. and then shifting` the gear 203 downwardly to diseugage it from the shaft 'ltltw and to clutch it to shaft 136.

lVithout further analysis, the foregoing; will so fully reveal the gist of this invention that others can. by applying,f current knowledge, readily adapt it for various utilizations by retaining one or more of the features that, from the standpoint of the prior art. fairly constitute essential characteristics of either the generic or speci ll aspects of this invention :ind.therefore.such aflaptai ions should be. and are intended to be. eon'inrehended within the nieanin;,r and range of equivalency of the following claims.

Having thus revealed this invention. l claim as new and desire to secure 'the frillowinga combinations and elements. or eouivalents thereof. b v Letters Patent `of the United State-:1

1. A machine tool combining a drill spin- CII llO

o (Del dle; a unidirectional drive therefor; a tap spindle; a reversible drive for said tap spindle; means actuated b v the tap spindle drive for giving the tap spindle axial movements in reverse directions; and means actuated by the tap spindle drive for feeding the drill spindles axially.

E2. A machine tool combining a drill spindle; a unidirectional drive therefor; a tap spindle; a reversible drive for rotating said tap spindle in reverse directions; means for giving to the 'tap spindle feeding movements in synchronism with its rotation; means actuated by the tap spindle drive for feeding the drill spindle axially in one direction; and resilient means for .moving the drill spindle in the opposite direction.

A machine tool combining a drill spin-- dle; a unidirectional drive therefor; a tap spindle; a reversible drive for rotating said tap spindle in reverse directions; means for giving to the tap spindle feeding movements in synchronism with its rotation; cam-actuated means controlled by the 'tap spindle rotating means for giving the drill spindle a feeding movement: and independent means to give the drill spindle a return movement.

4. A machine tool combining a plurality of rotatable and translatable drill spindles: means to rotate said drill spindles; a plurality of tap spindles; means to rotate said tap spindles in reverse directions; a pressure plate acting upon all of said drill-spindles; yielding means for retracting the drill spindles from the work; and means actuated by the tap spindle rotating means to move said plate in opposition to said yielding means to give to said drill spindles an axial movement to canse the drills carried thereby to be fed into the work.

A machine tool combining a drill spindle: a tap spindle; a unidirectional drive for the drill spindle; a reversible drive for the tap spindle; means for giving the tap spindle feeding movements in synchronism with its rotation; yielding means for retrac ing the drill spindle from the work; an arm acting in opposition to said yielding means to give the drill spindle a feeding movement toward the Work: a second arm operatively connected with the first mentioned arm; a slidingI cam acting upon said second arm to depress the first mentioned arm; a rack connected with said cam; and a pinion meshing with said rack and rotated by the tap spindle rotating mechanism for giving the cam its sliding movements.

G. A drilling and tapping machine combining a base; a column; a head; a lirst shaft extending lengthwise through said column and entering said base and head; povver means to rotate said shaft unidirectionally1 a drill spindle rotatably journaled in said head adriving connection between saidshaft and said drill spindle -to rotate the latter from the former; a second shaft journaled lengthwise of said column; a tap spindle rotatably journaled in said head; means adjacent the base to convert the unidirectional rotary motion of the first shaft into oppositely directed rotary motions in the second shaft; and means Within the head to transmit the oppositely directed motions of the second shaft to said tap spindle.

7. A machine tool combining a base; a column; a head secured upon said column; uni-directionally rotating shaft journaled lengthwise of said column and projecting into said head: a second shaft journaled lengthwise of said column and projecting into said head; means to give to said second shaft oppositely directed rotations; a tap spindle and a drill spindle rotatably journaled in said head means carried Wholly by the head for rotating the drill spindle from the first named shaft; and means carried Wholly by the head for rotating the tap spindle in forvvard and reverse directions and for giving both of said spindles axial feeding movements from said second shaft.

8. A machine tool combining a column; a unidirectiimally rotating shaft journaled lengthwise of said column and projecting thereabove; a second shaft journaled lengthwise of said column and projecting thereabove; means to give to said second shaft oppositely directed rotation; a tool-head; a drill spindle and a tap spindle rotatably journaled in said head; gear trains carried by said head and operatively connected With each of said spindles; and means permittng said head -to be removably secured upon said column With the initial gear of the drill spindle driving vtrain in engagement with the unidirectionally rotating shaft and with the initial gear of the tap spindle driving -train in engagement with the second shaft.

9. A machine tool combining a column; a uui-directionally rotating `element supported by the column; a multi-directionally rotating element supported by the column; a toolhead; a series of drill spindles and a series of `tap spindles rotatably journaled in said tool-head; a drivingl train for each of said series; means permitting said tool head to be secured upon said column with the primemover of the drill spindle driving train in operative relation -ivith the unidirectionally rotated element and with the prime-mover of the tap spindle driving train in operative relation with the Imulti-directionally rotating element; and mains permitting the removal of said head from said column and substitution therefor of another head equipped with differently arranged drill and tap spindles but with similar driving trains. the prime movers of the driving trains of the substitute head also being adapted to be driven by the uni-directionally and multidirectionally1 rotating elements.

l0. A machine tool combiningl a column; a uni-direetionally rotating element supported by the column; a multi-directionally rotating element supported by the column a tool-head supported upon the column and comprising a gear chest and a cap section: a drill spindle and a tap spindle rotatably and translatably journ aled in said tool head; a tirst rear train Within said gear chest connecting said nnidirectionally rotating element with said drill spindle; a second gear train Within said gear chest connecting said multi-directionaliy rotating element with said tap spindles; and means within said cap section to give to said drill and tap spindles axial feeding' movements.

11. A machine tool combining a plurality of rotatable spindles; a uni-directional drive 'tor said spindles: a multi-directional drive, tor said spindles and means permitting either ot said drives selectively7 to be rendered effective.

l2. A machine tool combining a tool-head: spindle bearings provided by said tool head; means permitting either drill spindles or tap spindles to be inserted into and supported in said bearings; a uni-directional drive embodied in said tool head and adapted to rotate drill spindles; a multi-directional drive embodied in said tool head and adapted to rot ate tap spindles in forward and reverse directions: and means permitting either ot said drives selectively to be rendered etiective.

1.3. A machine tool combining a tool head; a plurality of spindles rotatably journaled in said head: a uni-directional spindle drive: a multi-directional spindle drive; means permitting' either of said drives selectively to be connected with all of said spindles: and means permitting' one of said drives to be connected with one of said spindles while the other drive is connected with another of said spindles.

14. An interchangeable drilling and tapping' machine combining a tool head: a prime mover: two individual trains ol' mechanism extending' trom said prime mover into said tool head: one ot said trains ot'r mechanism operating' imi-directionally and the other operating multi-directionally: a plurality ot tool spindles rotatably journaled in said toolhead: and means pern'iitting either ot said trains of mechanism selectively to be connected With said tool spindles.

l5. A combination drillingr and tapping machine combining a tool head; a drill spindle and a tap-spindle rotatably and translatably journaled in said tool-head; an oscillatingr gear segment: a gear connection between said segment and said tap spindle to rotate the latter in reverse direction by the oscillatory motion of said gear segment; a uni-directional drive for the drill spindle; a

cam on said gear segment; and means actuated by said cam as the segment is moved in one direction to effect axial movement of the drill-spindle.

16. A con'ibination drilling and tapping inaehine combining :i drill spindle; a` tap spindle: an oscillatinfji` gear segment; a gear c .\nncction between the segment and said tap spindle to rotate the latter in forward and reverse directions, by the oscillatory motions of said gear segment a uni-directional drive for said drill spindle: yielding means for retracting the drill spindle trom the work; a member operatively connected with the drill spindie; a caln on said gear segment; and means actuated by said cam as the zgear segment is moved in a direction to rotate the tap spindle forwardly to mover said member thereby to cause it to move said drill spindle toward the work in opposition to said yielding means.

i7. A drilling and tapping machine combining a trame: a tool-head supported thereon: a drill spindle and a tap spindle rotatably and translatably journaled in said tool head; an oscillatory `fear segment; a `rear connection between said gear segment and said tap spindle to rotate the latter in reverse directions by the oscillatory motions of said segment: a uni-directional drive for said drill spindle; a cam on said gear segment; means actuated by said cam as the segment is moved in one direction to ellect a feeding movement ot the drill spindle: and means to prevent lateral movement et' said gear segment by the back pressure ol' the work on the drill.

18, A drilling' and tapping machine combining a trame: a tool-head supported thereon: a drill spindle and a tap spindle rotatably and translatably journaled in said tool head; an oscillatory gear serment; a gear connection between said gear segment and said tap spindle to rotate the latter in reverse directions by the oscillatory motions ot said segrment; a uni-directional drive for said drill spindle: a cani on said gear segment; means actuated b v said cam as the segment is moved in one direction to efteet a feeding movement ot the drill spindle: and means to transmit to the trame the baalt pressure oi' the work on the drill. thereby preventing` lateral movement. of the gear-segment.

19. A drillingr and tapping machine combining a. trame: a tool-head supported thereon a drill spindle and a tap spindle rotatably and translatably journaled in said tool head; an oscillatory gear segment; a gear connection between said lgear segment and said tap spindle to rotate the latter in reverse directions by the oscillatory motions ot' said see'- ment; a uni-directional drive tor said drill spi ndle; an arcrate cam on said gear segment; a roller tracking' said arcuate cam and moved laterally thereby as the segment is oseillated; an arm upon whieh the roller is supported; means actuated by the movement of the arm to effect a feeding movement of the drill spindle; an arcuate rib on said .segment opposite said arcuate cam; and a similar rib on the` frame contacting with said iirst named rib to receive the lateral thrust on the segment caused by the back pressure oi' the work on the drill.

20. A machine tool combining a column; a tool-head removably secured upon said column; a plurality of rotatable tool-spindles arranged in said head; a rotatable work table; a prime mover; means actuated by said prime mover to rotate said tool spindles; means aotuated by said prime mover to index said Work-tablet() present a work piecesuceessively to tools carried by said tool spindles; means permitting said tool head to be removed from said column and replaced by a similar head having tool spindles arranged differently from the arrangement in the first named head butalsoadapted to be ydriven `from said prime-mover; and means Vfor varying theextent ot angular movement ol said xvorlvtable in accordance with the location of the tool spindles in the substitute toohheadn In Witness whereof, I have hereuntosubscribed my name.

ROBERT M. GALLOVAYJ 

